Rakudo Star 2012.09 released

2012-09-30

On behalf of the Rakudo and Perl 6 development teams, I'm happy to announce the September 2012 release of "Rakudo Star", a useful and usable distribution of Perl 6. The tarball for the September 2012 release is available from http://github.com/rakudo/star/downloads. A Windows .MSI version of Rakudo star will usually appear in the downloads area shortly after the tarball release.

In the Perl 6 world, we make a distinction between the language ("Perl 6") and specific implementations of the language such as "Rakudo Perl". This Star release includes release 2012.09.1 of the Rakudo Perl 6 compiler, version 4.6.0 of the Parrot Virtual Machine, and various modules, documentation, and other resources collected from the Perl 6 community.

Some of the new features added to this release include:

Basic macro support!

Support for Perl 5 (m:P5/.../) regex syntax!

Indirect type names in routine and type declarations are supported.

We support the "is export" trait on constant declarations.

The "is hidden" and base traits are supported.

Str.wordcase, is-prime, and expmod are implemented.

Compilation is slightly faster than before.

Tie-breaking with constraints selects the first matching constraint rather than demanding mutual exclusion.

Smart matching against Signature literals, and binding to Signatures in declarators.

This release also contains a range of bug fixes, improvements to error reporting and better failure modes. More exceptions are thrown as typed exceptions, and more meta-model errors have been fixed to properly report line numbers.

The following features have been deprecated or modified from previous releases due to changes in the Perl 6 specification, and are being removed or changed as follows:

Iterable is now a role instead of a class, and no longer inherits from Cool.

Parameters preceded by a | or \ can no longer have a sigil.

IO::Path.dir (which returns the directory part of the path) has been renamed to IO::Path.directory. IO::Path.dir will be removed or re-purposed.

The Str.ucfirst builtin is deprecated; it will be replaced by Str.tc.

The (experimental) LAZY statement prefix will soon be removed.

Leading whitespace in rules and under :sigspace will no longer be converted to <.ws> . For existing regexes that expect this conversion, add a <?> in front of leading whitespace to make it meta again.

The ?-quantifier on captures in regexes currently binds the capture slot to a List containing either zero or one Match objects; i.e., it is equivalent to "* 0..1". In the future, the ?-quantifier will bind the slot directly to a captured Match or to Nil. Existing code can manage the transition by changing existing ?-quantifiers to use "* 0..1", which will continue to return a List of matches.

There are some key features of Perl 6 that Rakudo Star does not yet handle appropriately, although they will appear in upcoming releases. Some of the not-quite-there features include:
* advanced macros
* threads and concurrency
* Unicode strings at levels other than codepoints
* interactive readline that understands Unicode
* non-blocking I/O
* much of Synopsis 9

In many places we've tried to make Rakudo smart enough to inform the programmer that a given feature isn't implemented, but there are many that we've missed. Bug reports about missing and broken features are welcomed at rakudobug@perl.org.

See http://perl6.org/ for links to much more information about Perl 6, including documentation, example code, tutorials, reference materials, specification documents, and other supporting resources. A draft of a Perl 6 book is available docs/UsingPerl6-draft.pdf in the release tarball.